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HomeDatabaseMysql Tutorial实战经验为何数据库归档日志名称为空

实战经验为何数据库归档日志名称为空

Jun 07, 2016 pm 03:24 PM
setsqlActual combatArchivedatabaselogexperience

SQL set pages 100 lines 120 SQL SELECT DISTINCT DECODE(NAME, NULL, 'NULL', NAME) FROM V$ARCHIVED_LOG; DECODE(NAME,NULL,'NULL',NAME) -------------------------------------------------------------- NULL SQL SHOW PARAMETER LOG_ARCHIVE_DEST_1 N


SQL> set pages 100 lines 120
SQL> SELECT DISTINCT DECODE(NAME, NULL, 'NULL', NAME) FROM V$ARCHIVED_LOG;

DECODE(NAME,NULL,'NULL',NAME)
--------------------------------------------------------------
NULL

SQL> SHOW PARAMETER LOG_ARCHIVE_DEST_1

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_1 string LOCATION=/data1/archivelog
log_archive_dest_10 string 


将数据库的归档目录改回到ASM上,马上就可以看到新的归档日志的名称:

SQL> ALTER SYSTEM SET LOG_ARCHIVE_DEST_1 = 'LOCATION=+DISK/testrac/' SCOPE = MEMORY SID = 'testrac1';


系统已更改。

SQL> ALTER SYSTEM SET LOG_ARCHIVE_DEST_1 = 'LOCATION=+DISK/testrac/' SCOPE = MEMORY SID = 'testrac2'; 

系统已更改。

SQL> ALTER SYSTEM ARCHIVE LOG CURRENT;

系统已更改。

SQL> SELECT NAME, COUNT(*) FROM V$ARCHIVED_LOG GROUP BY NAME;

NAME COUNT(*)
------------------------------------------------------------ ----------
250
+DISK/testrac/2_208_618591128.dbf 1
+DISK/testrac/1_292_618591128.dbf 1

关闭数据库,使刚才的归档参数的修改失效,归档路径恢复到本地,再次查询:

SQL> SELECT NAME, COUNT(*) FROM V$ARCHIVED_LOG GROUP BY NAME;

NAME COUNT(*)
------------------------------------------------------------ ----------
250
/data1/archivelog/2_209_618591128.dbf 1
/data1/archivelog/1_293_618591128.dbf 1
+DISK/testrac/2_208_618591128.dbf 1
+DISK/testrac/1_292_618591128.dbf 1

目前仍然可以看到所有的归档日志名称,下面尝试用rman删除所有的归档日志。

SQL> SELECT NAME, COUNT(*) FROM V$ARCHIVED_LOG GROUP BY NAME;

NAME COUNT(*)
------------------------------------------------------------ ----------
256

通过rman删除后,归档日志名称再次变成空值。

这个问题在metalink上也没有找到类似的描述,个人怀疑和ASM有关。
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